Diabetes, Vol 46, Issue 12 2082-2087, Copyright © 1997 by American Diabetes Association
Cholesteryl ester transfer protein gene polymorphism is a determinant of HDL cholesterol and of the lipoprotein response to a lipid-lowering diet in type 1 diabetes
RP Dullaart, K Hoogenberg, SC Riemens, JE Groener, A van Tol, WJ Sluiter and BK Stulp
Department of Endocrinology, University Hospital Groningen, The Netherlands.
The TaqIB cholesteryl ester transfer protein (CETP) gene polymorphism
(B1B2) is a determinant of HDL cholesterol in nondiabetic populations.
Remarkably, this gene effect appears to be modified by environmental
factors. We evaluated the effect of this polymorphism on HDL cholesterol
levels and on the lipoprotein response to a linoleic acid-enriched,
low-cholesterol diet in patients with type 1 diabetes. In 44 consecutive
type 1 diabetic patients (35 men), CETP polymorphism, apolipoprotein (apo)
E genotype, serum lipoproteins, serum CETP activity (measured with an
exogenous substrate assay, n = 30), clinical variables, and a diet history
were documented. The 1-year response to diet was assessed in 14 type 1
diabetic patients, including 6 B1B1 and 6 B1B2 individuals. HDL cholesterol
was higher in 10 B2B2 than in 14 B1B1 homozygotes (1.63 +/- 0.38 vs. 1.24
+/- 0.23 mmol/l, P < 0.01). HDL cholesterol, adjusted for triglycerides
and smoking, was 0.19 mmol/l higher for each B2 allele present. CETP
activity levels were not significantly different between CETP genotypes.
Multiple regression analysis showed that VLDL + LDL cholesterol was
associated with dietary polyunsaturated:saturated fatty acids ratio (P <
0.02) and total fat intake (P < 0.05) in the B1B1 homozygotes only and
tended to be related to the presence of the apo E4 allele (P < 0.10). In
response to diet, VLDL + LDL cholesterol fell (P < 0.05) and HDL
cholesterol remained unchanged in 6 B1B1 homozygotes. In contrast, VLDL +
LDL cholesterol was unaltered and HDL cholesterol decreased (P < 0.05)
in 6 B1B2 heterozygotes (P < 0.05 for difference in change in VLDL +
LDL/HDL cholesterol ratio). This difference in response was unrelated to
the apo E genotype. Thus, the TaqIB CETP gene polymorphism is a strong
determinant of HDL cholesterol in type 1 diabetes. This gene effect is
unlikely to be explained by a major influence on the serum level of CETP
activity, as an indirect measure of CETP mass. Our preliminary data suggest
that this polymorphism may be a marker of the lipoprotein response to
dietary intervention.